It's almost impossible to find a new "real" 8" 3/4HP bench grinder these days. All of the 8" 3/4HP bench grinders you see for sale at HD, Lowes or HF are really 1/2 HP or less. You can get real 3/4HP grinders from Dayton, but you're looking at $300 + shipping.
A Baldor is a TOTL tool, and if it's labeled 3/4HP, it's going to be 3/4HP. I would say $350 is a marginal, but still an acceptable price. It's bit on the high side for what is clearly an older grinder with a lot of miles on it and 7 hours of driving. If it were $200-250 with the base and a smooth runner - I'd say that'd be a screaming deal.
Basically, I wouldn't feel ripped off buying it, but I wouldn't feel like I made out like a bandit either.